OF LABRADOR AND MAINE. 243 



The following species were collected by my friend Mr. C. G. Atkins, from the 

 river bank just above the dam. 



Pccten islandicus Linn. Abundant as usual. 



Leda portlandica Hitchc. Abundant. 



Mytilus edulis Linn. Abundant. 



Ostrava canadensis. This species is inserted on the authority of Professor Desor, as speci- 

 mens collected by him are in the Museum of this Society. 



Astarte compressa Linn. (A elliptica Brown.) Common. 



Astarte semisulcata Leach. Frequent. 



Astarte striata Leach. Rare. 



Cardium pinnulatum Conr. Not common ; also in a collection made by Professor Desor, 

 in the Museum of this Society. 



Serripes gronlandicus Beck. Frequent. 



Macoma gronlandica Stimps. Common ; showing that the deposit was near the upper 

 level of the Laminarian zone, as also does the presence of large Myce and Mytili 



Macoma sabulosa Sprengel. Common and large. 



Mya truncata Linn., var. uddevallensis. Common. 



Mya armaria Linn. Abundant and large. 



Saxicava arctica Desh. (S. rugosa Linn.) Common. 



Natica clausa Sowb. 



Naiica gronlandica (Beck.) Both species were not uncommon. 



Buccinum gronlandicum Hancock. Of the usual frequency. 



Buccinum tenue Gray. {Buccinum scalariforme Beck.) One imperfect specimen. 



Buccinum glaciate Linn. One specimen occurred. 



Buccinum undulatum Moller. A specimen collected by Desor is in the collection of this 

 Society. 



Balanus Humeri Ascan., collected by Mr. C. G. Atkins, occurred at Vassalboro. 



The deposits of Gardiner possess great interest owing to their unusual thick- 

 ness, and the rich assemblage of marine invertebrates which occur from the 

 lowest to the higher strata, and from the occurrence of the teeth of the bison, and of the 

 walrus, which were dug out of the beds at a distance of fifteen feet from the top of the 

 clay, during Sir Charles Lyell's second visit to this country. He states that the teeth of 

 the bison were forwarded to London, where they were identified by Professor R. Owen. 

 The intermingling of the bones of the walrus and bison in the same beds, shows the great 

 range both of Arctic and Temperate forms during this period. It is parallelized by the 

 similar intermixture of Leda truncata, now peculiar to the seas of Spitzbergen, with shells, 

 for example, Cardium pinnulatum, more characteristic of the present fauna of Maine. This clay 

 formation rises in conical hills of over one hundred feet elevation above the level of the 

 river, rising from the railroad, which is eighteen feet above high water, and twenty feet 

 above the sea level, while their summits are capped by thick beds of coarse marine gravels 

 often thirty feet thick. The marine gravel which overlies them has been greatly denuded 

 by the action of the river which has formed out of this material the series of river terraces 

 which rise about half way up to the summit of the hills. This clay formation extends con- 

 tinuously down the river to the coast, constantly spreading out into a broader area and 

 rising into low hills and broad undulating fields as it approaches the coast, there present- 

 ing beds of similar lithological characters, and with much the same zoological assemblages, 

 as at Brunswick and Saco. 



MEMOIRS DOST. SOC. NAT. HIST. Vol. I. Pt. 2. 62 



